When does ENVIRONMENT VARIABLE expansion occur in set?
On the command line (and in batch files), environment variable expansion occurs when the command is read. This sounds obvious at first, but it has its own consequences. In the online documentation for SET, one such consequence is spelled out:
Can you set environment variables in an ENV file?
If you set an environment variable in an intermediate container using bash (RUN export VARI=5 && …) it will not persist in the next command. There’s a way to work around that. An env_file, is a convenient way to pass many environment variables to a single command in one batch. This should not be confused with a .env file.
How to expand the environment variable in registry?
Environment.ExpandEnvironmentVariables. If you control the creation of the registry value, store it as an expandable string in the registry and the registry API will automatically expand it for you. Another option is to use Environment.ExpandEnvironmentVariables. This will replace all environment variables with their values:
How are variables set in the build environment?
All variables are set as environment variables in the build environment, and they are accessible with normal methods that are used to access such variables. In most cases bash or sh is used to execute the job script. To access environment variables, use the syntax for your Runner’s shell.
When to use the < < EOL operator in shell?
In the latter case, the character sequence ` ewline’ is ignored, and `\\’ must be used to quote the characters `\\’, `$’, and “’. If the redirection operator is `<<-‘, then all leading tab characters are stripped from input lines and the line containing DELIMITER.
How to enable delayed expansion in / V /?
For that, you use “delayed expansion”, which is enabled by the /V command line option or by using the SETLOCAL ENABLEDELAYEDEXPANSION command in a batch file. C:\\> copy con “%TEMP%\\helper.cmd” SETLOCAL ENABLEDELAYEDEXPANSION set VAR=before set VAR=after & echo immediate:%VAR%, delayed:!VAR! ENDLOCAL ^Z 1 file (s) copied.
When do you use% VAR% in set?
In the online documentation for SET, one such consequence is spelled out: would never display the message, since the %VAR% in both “ if ” statements is substituted when the first “ if ” statement is read, since it logically includes the body of the “ if “, which is a compound statement.